The Zöllner Illusion is a classic optical illusion named after its discoverer, the German astrophysicist Johann Karl Friedrich Zöllner. This illusion showcases how our perception of parallel lines can be distorted by other intersecting lines.
In the Zöllner Illusion, you’re presented with a series of long diagonal lines, which are indeed parallel. However, shorter lines are superimposed on these diagonal lines at an angle. The presence and positioning of these shorter lines create an impression that the longer diagonal lines are not parallel, but rather are converging or diverging.
In reality, the long diagonal lines remain perfectly parallel to each other, despite appearing otherwise. The illusion occurs because of the angle of the shorter lines intersecting the longer lines, which leads our brains to misinterpret the angles between the lines, causing a distortion in the perceived orientation of the long diagonal lines.
This phenomenon is a striking example of how context and surrounding elements can greatly influence our perception. It highlights that our visual system is not a straightforward interpreter of the world but involves complex neurological processes.